Sarcoscypha, the type genus of the family Sarcoscyphaceae (Pezizales,
operculate discomycetes, Ascomycotina), is well known in Great Britain as “scarlet-cups” by
its bright scarlet- or purple-red discs, “perhaps the most beautiful of British
ascomycetes” (Dennis 1978). The genus is widespread in north temperate and
boreal regions, but also occurs in (sub)tropical areas and in the southern
hemisphere. To the present knowledge, about 18 species can tentatively be
accepted world-wide, about 6 of which occur
within Europe and N-America. Many appear to be endemic to volcanic islands in
the subtropics. Though quite a high number of species (about 60) have
ever been combined in the genus Sarcoscypha,
many of these remained virtually unknown as they were often only collected a
single time, and especially the old descriptions are very inadequate. Often
redescriptions of the type material, if any exists, are lacking. Many of the
taxa have later been found to belong in other genera of the Sarcoscyphaceae, or
were referred to other families of the Pezizales, some even to the Helotiales.

Unlike most Pezizales, the
members of the Sarcoscyphaceae grow as saprophytes on dead woody plant material
(rarely woody fruits), in the case of Sarcoscypha on mostly damp, mossy
branches of broad-leaved, very rarely coniferous trees, that were fallen to the
ground. Most species of Sarcoscypha fruit in winter and early spring,
and are often already mature when still covered by snow.

Vital taxonomy

Although microscopical
differences observed in living specimens has indicated since about 1900 the existence
of several, macroscopically indistinguishable taxa within the temperate to
alpine-boreal zone of the northern hemisphere (Europe and North America), only
one large-cupped species of Sarcoscypha, S. coccinea, has currently been recognized in
this large area during many later decades. The diagnostic microscopical
characters supporting existence of different taxa mainly concern (1) striking
differences in the guttule (lipid) pattern of living ascospores, first observed
by Boudier (1903), (2) a very different germination behaviour of the ascospores
among collections (with or without forming conidia), first observed by Rosinski
(1953, corresponding case reported by Paden 1974 in Phillipsia), and (3) differently shaped spore ends. Strong
differences in conidial size were later observed in pure culture, and DNA
sequences supported existence of different taxa.

Baral (1984, Central
Europe), Harrington (1990, USA), Butterfill & Spooner (1995, Great
Britain), Pidlich-Aigner (1999, Austria), Öpik et al. (2000, Estland), G. &
Y. van Duuren (2003, 2004, Netherlands),Matočec & Kušan (2007,
Croatia) and B. & O. Perić
(2007) confirmed the observations of
Boudier and Rosinski, and showed that totally four different large-cupped
species exist in Europe and N-America (S. austriaca, S. coccinea,
S. dudleyi, S. jurana,
apothecial diameter 20-90 mm), three of them in Europe.
Both geographical distribution and host specifity differ severely among these
species. Two further species deviating by smaller apothecia and also smaller
ascospores exist in that area. One is perhaps endemic to the Macaronesian
islands (S. macaronesica,
unclear forms intermediate to S. coccinea appear to be characteristic of
the eumediterranean belt). The other species occurs in atlantic and
continental N-America east of the Rocky Mts. (S. occidentalis).

Both lipid pattern and
germination behaviour are vital characters, which means that they are difficult
or impossible to observe in dead herbarium material: (1) ascospore guttulation
severely alters in dead spores by fusion of the oil drops, and (2) presence of
germinated ascospores in fruit-bodies strongly depends on the development stage
of the preserved collection. Fresh samples can be kept moist until spores
germinate abundantly. If dried samples show fused oil drops and do not contain
germinated spores, the differences between the species bescome quite obscure.
As a consequence, herbarium taxonomists like Le Gal (1941) were unable to
confirm the differences as reported by Boudier and Rosinski.

Harrington (1990: 436)
wrote:“The importance of fresh material
for species diagnosis, especially for noting ascospore guttulation, cannot be
overstated. Although I had examined material (dried herbarium specimens) from
western North America I was not prepared to
recognize that group as a species distinct from the two, large eastern North
American species until I saw fresh (living) material.”Sarcoscypha represents one of the numerous examples of fungal
genera in which a sound taxonomy is only achieved on the basis of vital macro-
and especially microscopical characters gained from the study of fresh
collections (“vital taxonomy”).